The present invention relates generally to armament apparatus for aircraft, and, in a preferred embodiment thereof, more particularly relates to ammunition magazine apparatus for storing ammunition belts fed to aircraft-mounted machine guns, and to structure used to mount the magazine apparatus on the aircraft.
Disclosed in U.S. Pat. No. 4,893,545 (incorporated by reference herein) is an aircraft armament system representatively utilized in conjunction with a helicopter and including an elongated support plank, of a reinforced honeycomb metal construction, which longitudinally extends transversely through the cabin area of the helicopter, with opposite end portions of the plank projecting outwardly beyond opposite sides of the helicopter. longitudinally central portion of the plank within the cabin is secured to the helicopter, and the outwardly projecting plank ends each carry a 0.50 caliber machine gun pod, or a 7.62 mm machine gun, and a multi-tube rocket launcher.
Belted ammunition for the two plank-supported machine guns is carried within two elongated rectangular magazine boxes secured to the top side of the plank within the cabin area. The ammunition belt from each magazine box is routed outwardly through a cabin door and downwardly through a plank slot to the box's associated machine gun.
While this plank-based aircraft weaponry mounting system has proven to be a substantial improvement over conventional aircraft weaponry mounting systems, it has been found that certain problems, limitations and disadvantages are associated with both the conventional ammunition magazine box structures and the conventional method used to secure them to the support plank.
For example, each of the elongated, high capacity magazine boxes shown in U.S. Pat. No. 4,893,545 (when fully loaded with ammunition) is quite heavy, and typically requires more than two men to lift it into the cabin area and properly orient it on the support plank. This task is even more difficult in low light conditions.
Once in place, the two large magazine boxes are secured to the top side of the plank using conventional aircraft tie-down straps. This magazine attachment method has proven to be less than completely satisfactory from two primary standpoints. First, current military design criteria require, among other things, that the supported magazine box structures be able to withstand at least a 4G crash load. Conventional tie-down straps typically cannot meet this requirement. Additionally, despite its desirably high level of structural rigidity, the central support plank portion is subject to at least some degree of lateral (i.e., up and down) flexure during flight of the aircraft. When conventional tie-down straps are used to hold the magazine boxes directly against the plank, the flexure of the plank unavoidably transfers undesirable vertical bending forces to the magazine boxes. Magazine boxes must often be installed and removed at night under combat conditions. Tie-down straps would be difficult at best to install properly under these low light/stressful conditions.
Another problem relating to the use of conventional ammunition magazine box structures in this application arises from the high degree of weaponry mounting diversity provided by the plank-based system. For example, various combinations and arrangements of both 0.50 caliber and 7.62 mm machine guns (with or without rocket launchers) may be mounted on the outer plank ends. More specifically, depending upon the particular mission of the aircraft, the plank may be used to carry one 0.50 caliber machine gun, one 7.62 mm machine gun, two 0.50 caliber machine guns, two 7.62 mm machine guns, or one 0.50 caliber machine gun and one 7.62 mm machine gun.
This weaponry mounting diversity has heretofore required that, in transporting the helicopter and its associated armament system to a mission site, two pairs of the illustrated elongated ammunition magazine boxes (two each in 0.50 caliber and 7.62 mm sizes) be provided to accommodate whatever aircraft machine gun arrangement the particular mission might require. As can be envisioned, this requires an overall magazine box storage volume and weight approximately twice that of the weight and volume of the two magazine boxes illustrated in U.S. Pat. No. 4,893,545. Moreover, in certain instances a particular mission may not require that a full magazine box load of ammunition be carried on the aircraft for a given machine gun. This reduced ammunition requirement may, of course, be accommodated simply by only partially filling one of the large capacity boxes shown in such patent. However, when this is done, the empty portion of the box undesirably takes up cabin space which could be used for other purposes, and adds, in effect, dead weight to the overall aircraft load.
In view of the foregoing, it is an object of the present invention to provide an improved ammunition magazine box system, and associated mounting structure therefor, which eliminates or minimizes the above-mentioned and other problems, limitations and disadvantages heretofore associated with conventional magazine boxes of the general type described above.